Machine tool guard and/or safety shield

ABSTRACT

A machine tool guard and/or safety shield to protect the machine operator from flying chips, coolant liquids, such as oils, and other materials, and to provide protection from contact with the machine moving parts, wherein the device is readily attachable to a machine tool and is provided with a body having a slot for receiving a shield or protective guard removably secured thereto, and wherein the shield or guard is clamped by a plunger which is operated by a manual lever, and wherein the plunger is normally biased to retain the shield or guard, and wherein the plunger may be retracted by manual means to permit release of the guard or shield.

United States Patent Smith et al.

[54] MACHINE TOOL GUARD AND/OR SAFETY SHIELD [72] Inventors: William Smith, 6 North 654 Pine, RR. 3, Bensenville, 111. 60106; Charles E. McGrath, 3552 West 115th Place, Chicago, 111. 60655 [22] Filed: June 7, 1971 [21] Appl. No.: 150,548

[52] US. Cl. ..90/11 R, 51/272, 269/254 R [51] Int. Cl ..B23c 9/00 [58] Field of Search ..90/11 R; 408/241 G; 51/268,

51/272; 144/251 A; 143/159 N; 269/254 R,

[56] References Cited UNITED STATES PATENTS 1,812,452 6/1931 Shaw ..5l/272X [4 1 Nov. 21, 1972 Primary Examiner-Gil Weidenfeld Attorney-Max R. Kraus [5 7] ABSTRACT A machine tool guard and/or safety shield to protect the machine operator from flying chips, coolant liquids, such as oils, and other materials, and to provide protection from contact with the machine moving parts, wherein the device is readily attachable to a machine tool and is provided with a body having a slot for receiving a shield or protective guard removably secured thereto, and wherein the shield or guard is clamped by a plunger which is operated by a manual lever, and wherein the plunger is normally biased to retain the shield or guard, and wherein the plunger may be retracted by manual means to permit release of the guard or shield.

11 Claims, 5 Drawing Figures PATENTED 1973 3.703.124

FIG. 3

64 I Inventor ILLIAM SMITH BY CHARLES E. McGR ATTY.

MACHINE TOOL GUARD AND/OR SAFETY SHIELD BRIEF SUMMARY OF THE INVENTION This invention relates to a device which may be readily attached or secured to a machine tool to support a shield or guard so that the shield or guard is positioned between the cutting tool and work piece on the one hand, and the machine operator on the other hand.

In connection with metal cutting machines, such as milling machines and the like, the flying metal produced as a result of the cutting operation and the splattering of the oils and/or coolant liquids presents a hazard to the operator of the machine. In addition, the machine operator may accidentally contact the moving machine parts with resultant injury. One of the objectives of this invention therefore is to provide a device which may be mounted and/or positioned and secured on a machine which does such cutting and provide a replaceable shield or guard which protects the operator from the flying chips, liquids, oils and the like, as well as serve as a barrier between the operator and the cutting tool to prevent accidental contact with the moving parts.

Another object of this invention is to provide a device which will support a guard or shield which may be readily inserted in the device and which also may be readily removed and replaced after it has become deficient in its use.

Guards or shields heretofore used are of a more or less permanent nature and in due time the flying chips and liquids and oils that. come in contact with the guard or shield tend to impair the efficiency of the guard or shield. With this invention the guard or shield can be made of a material such as cardboard or the like which serves as a protective member between the operating tool and the operator but which has the advantage of being readily replaceable with other like shields or guards at a minimum expense and in a minimum of time.

Another object of this invention is to provide a unit which may be readily positioned relative to the cutting tool and the work to best protect the operator from the hazards of the cutting operation.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a fragmentary perspective view showing the use of the device forming this invention supported on a milling machine and showing the guard or shield positioned and supported in said device so as to protect the operator.

FIG. 2 is a top plan view with a portion in section to show particularly the operation of the plunger.

FIG. 3 is a sectional view taken on line 3-3 of FIG. 2.

FIG. 4 is a view taken on line 44 of FIG. 3, and

FIG. 5 is a rear elevational view of a device similar to that previously described except that it is held by magnets.

The device or unit is generally indicated at 10 and is preferably made of metal and machined, although it may be made of any other suitable material. It includes a body 12 having a vertically extending slot or recess 14 adjacent the front thereof which extends along the length of the body, which slot has a bottom 16. The

bottom 18 of the body is substantially flat, as is also the rear 20. The top 22 of the body adjacent the front is likewise flat with the rear portion 24 of the top stepped down.

The body is provided with a pair of horizontally and transversely extending bores 26 with each bore adjacent the opposite end of the body. The front of each of the bores communicates with a reduced bore 28 providing a shoulder 29 therebetween. The reduced bore 28 communicates with the vertical slot 14. The rear of the bore 26 is internally threaded as at 30 to threadedly receive an externally threaded retainer 32 provided with a central opening 33.

A plunger generally indicated at 34 is horizontally positioned in each of the bores 26 and the plunger has an annular collar 36 affixed thereto which is spaced from the front of the plunger. The front end 37 of the plunger is adapted to be positioned in the reduced bore 28, with the rear portion 38 of the plunger extending through the central opening 33 of the retainer 32.

A coil spring 40 encircles each of the plungers, with one end of the spring engaging the collar 36 and the opposite end engaging the retainer 32 to normally urge or bias the plunger forwardly until it is stopped by engagement of the collar 36 with the shoulder 29. In this position of the plunger, the front end thereof extends into the recess 14 and engages the shield or guard 41 supported in the recess.

A lever bar generally indicated at 42 is secured to the rear of the plungers 34, with the lever bar extending at the rear of the body and along the length thereof. The lever bar is operated by a manually operated cam lever generally indicated at 44 for the purpose of either retracting the plungers or releasing them so that they operate to engage the shield or guard 41. More specifically, the rear of the plunger 34 has an internally threaded bore 46 which receives a threaded screw 48 extending through an opening in the lever bar 42 with the head 49 of the screw confined within the enlarged recess in the lever bar to thus secure the lever bar 42 to the rear of the two plungers 34.

The lever bar 42 is provided with a horizontally extending slot 50 which pivotally receives the cam head 52 of the lever. A vertical pin 54 is anchored to the lever bar and passes through an opening in the head 52 of the lever to pivotally support the lever. The head 52 -of the lever 44 has a front flat surface 56 having a radius which continues rearwardly to form a top camming surface 58. The front surface 56 is substantially parallel with the handle portion of the lever 44 and is at right angles to the top camming surface 58. Operating the lever 44 will in turn operate the plungers 34.

As shown in full lines in FIG. 2, with the handle 60 of the lever 44 positioned parallel to the lever bar 42 the front surface 56 of the head 52 of the lever will be parallel with but spaced slightly from the rear of the body. In this position the plungers will be free so that the springs 40 thereon will urge the plungers 34 forwardly so that the front ends 37 thereof extend into the slot and engage the guard or shield 41 supported therein to lock it in position. When it is desired to remove or withdraw the guard or shield from the slot, I

the lever 44 is pivoted to the position shown in dotted lines in FIG. 2, wherein the camming surface 58 of the head contacts with and is parallel to the rear wall of the body. This pushes or moves the lever bar 42 rearwardly in a spaced relation to the rear of the body and simultaneously retracts the plungers to the position shown in FIG. 3, wherein the front ends of the plungers are withdrawn from the slot 14 to release the guard or shield 41 so that it can be removed from the slot. Pivoting the lever 44 to the full line position of FIG. 2 will again release the plungers 34, as previously described. The plungers are thus reciprocally movable by manipulating the lever 44.

The shield or guard 41 may be of any material, preferably cardboard or the like, which is economical and which may be readily replaceable when it becomes spattered with oil and the like. Also, the shield may be shaped to form inturned ends, as shown in FIG. 1.

This invention may be applied to any machine tool to serve as a guard for the flying metal chips and spattering oils. As shown in FIG. 1, it is applied to a milling machine 62 and is supported on the work table 64 of the machine. The conventional work table 64 is provided with spaced parallel extending T-shaped slots 66 and the device 10 is secured to one of said slots by the following means.

The body 12 is provided with a vertical bore 6 which is positioned inwardly of the spaced plungers. A bolt 70 extends through the bore 68 and the head 71 of the bolt bearing on the recessed top portion of the body 12 and with the threaded end of the bolt engaged by a square-shaped nut 72. As best shown in FIG. 3, the nut 72 is confined in the T-shaped slot 66, being slipped in endwise of the slot, and by rotating the bolt 70 it is tightened relative to the nut to lock the body to the work bench 64. The unit may be positioned anywhere along the length of the work bench and may be removed therefrom when desired. The shield 41 would thus be positioned rearwardly of the cutting tool T and the piece P being cut and forwardly of the operator to prevent the chips or spattering oil from striking the operator. The shield or guard 41 would thus deflect same.

The device or unit 10 may be turned to various angles relative to the work table and be locked in such positions to deflect the chips and oils. The guard or shield 41 also protects the operator from accidentally contacting the rotating cutting tool T.

FIG. shows a modification in which in lieu of securing the unit by bolts it may be secured by magnets 14 which are positioned against the underside of the body, with the magnets resting on work bench 64. The use of magnets is advisable when the work bench does not have slots like that shown in FIG. 1. In such condition the bolts and nuts may be eliminated and in lieu thereof the magnets are used.

What is claimed is:

1. A machine tool guard comprising a body having a slotted or recessed portion adjacent the front of said body for receiving a shield or guard removably secured in said slot, a plunger horizontally supported in said body and having means at the front of said plunger adapted to extend into said slot to engage the shield or guard to retain it in position in said slot, means for retracting said plunger to disengage said plunger from said shield and to permit removal of said shield or guard, and means for retaining said body on the surface of Ehe machine tool or the like.

. A device asset forth m claim 1 in which a plurality of plungers are horizontally supported in the body with said plurality of plungers simultaneously retractable.

3. A device as set forth in claim 1 in which the plunger is spring biased to normally urge said plunger forwardly to extend into the slot to engage the guard or shield.

4. A device as set forth in claim 3 in which the means for manually retracting the plunger includes a lever which is pivotally connected to a lever bar secured to the rear of the plunger.

5. A device as set forth in claim 2 in which a bar is secured to the rear of the plungers with the bar supported rearwardly of the body and in which the bar supports a manually operated lever which will move the bar rearwardly in spaced relation to the rear of the body to retract the plungers and wherein the plungers are spring biased to normally' urge them forwardly except when said lever acts to retract the plungers.

6. A device as set forth in claim 1 in which the body is provided with means for attaching the unit to a cutting machine.

7. A device as set forth in claim 6 in which the body has a vertical bore adapted to receive a bolt connected at its lower end to a nut, which nut is secured to the work table of the machine.

8. A device as set forth in claim 6 in which the body is detachably secured to a surface of the machine tool by magnetic means.

9. A device as set forth in claim 1 in which the guard or shield is formed of a strip of board or the like which is capable of being manually bent to a desired shape at its opposite ends.

10. A device as set forth in claim 1 in which the plunger is spring biased to normally urge same forwardly so that the front end of the plunger extends into the recess for a locking engagement with the guard and in which the rear of the plunger is attached to a bar extending rearwardly of the body and in which a lever is pivotally supported on said bar to move said bar relative to said body to either retract the plunger or to move the plunger forwardly.

11. A device as set forth in claim 10 in which the lever has a cammed head adapted to engage the rear of the body to move and space the bar rearwardly from the rear of the body to thereby retract the plunger. 

1. A machine tool guard comprising a body having a slotted or recessed portion adjacent the front of said body for receiving a shield or guard removably secured in said slot, a plunger horizontally supported in said body and having means at the front of said plunger adapted to extend into said slot to engage the shield or guard to retain it in position in said slot, means for retracting said plunger to disengage said plunger from said shield and to permit removal of said shield or guard, and means for retaining said body on the surface of the machine tool or the like.
 1. A machine tool guard comprising a body having a slotted or recessed portion adjacent the front of said body for receiving a shield or guard removably secured in said slot, a plunger horizontally supported in said body and having means at the front of said plunger adapted to extend into said slot to engage the shield or guard to retain it in position in said slot, means for retracting said plunger to disengage said plunger from said shield and to permit removal of said shield or guard, and means for retaining said body on the surface of the machine tool or the like.
 2. A device as set forth in claim 1 in which a plurality of plungers are horizontally supported in the body with said plurality of plungers simultaneously retractable.
 3. A device as set forth in claim 1 in which the plunger is spring biased to normally urge said plunger forwardly to extend into the slot to engage the guard or shield.
 4. A device as set forth in claim 3 in which the means for manually retracting the plunger includes a lever which is pivotally connected to a lever bar secured to the rear of the plunger.
 5. A device as set forth in claim 2 in which a bar is secured to the rear of the plungers with the bar supported rearwardly of the body and in which the bar supports a manually operated lever which will move the bar rearwardly in spaced relation to the rear of the body to retract the plungers and wherein the plungers are spring biased to normally urge them forwardly except when said lever acts to retract the plungers.
 6. A device as set forth in claim 1 in which the body is provided with means for attaching the unit to a cutting machine.
 7. A deVice as set forth in claim 6 in which the body has a vertical bore adapted to receive a bolt connected at its lower end to a nut, which nut is secured to the work table of the machine.
 8. A device as set forth in claim 6 in which the body is detachably secured to a surface of the machine tool by magnetic means.
 9. A device as set forth in claim 1 in which the guard or shield is formed of a strip of board or the like which is capable of being manually bent to a desired shape at its opposite ends.
 10. A device as set forth in claim 1 in which the plunger is spring biased to normally urge same forwardly so that the front end of the plunger extends into the recess for a locking engagement with the guard and in which the rear of the plunger is attached to a bar extending rearwardly of the body and in which a lever is pivotally supported on said bar to move said bar relative to said body to either retract the plunger or to move the plunger forwardly. 